I like the 45-70 for the fact you can get lighter loads for it off the shelf as mentioned in one of the above posts. You can also get full bore loads that will get close to 458 Win Mag factory loads. Either cartridge will take down anything you care to hunt in North America. I reload for the 45-70, but sometimes I get lazy and grab a box of the cowboy loads to plank with at the range which is something you can't do with the 450 Mar.